I can think of one application of a trillion dollar AI. A starship computer. Think of a starship one that takes thousands of years to arrive at the nearest star, it is propelled by an ion drive that is powered by an atomic fission reactor, part of the payload is an O'Neil colony, an ISland One Bernal Sphere, but it is not a generation ship, as the journey to the nearest star would take longer that recorded history, instead we have a computer AI that monitors the ship and the environment within the Bernal sphere, and when the time of final approach to the star system is arrived at, frozen human embryos are revived and implanted in artificial wombs in the starship, babies are raised to adulthood by the ship's computer, and sometime, perhaps by the year 10,000 AD the first humans set down on the terraformed surface of a planet orbiting Alpha Centauri A.

I'm sorry I missed the part where you explained how this would be beneficial for anyone at all? Either the people paying for it or the poor creatures generated at the other end.